Three people have died after picking up listeria infections from pre-packed sandwiches, Public Health England (PHE) has reported.
Six people in total have fallen ill with the infection – all of whom were seriously ill hospital patients in England. No infections have been found in Wales, Scotland or Northern Ireland.
The source of the outbreak is thought to be linked to Staffordshire sandwich producer The Good Food Chain which has now voluntarily ceased production.
The Good Food Chain was supplied with meat from North Country Cooked Meats, which has had a positive result for the outbreak strain of listeria.
Nick Phin, PHE deputy director at the national infection service, said: “Our thoughts are with the families of those patients who have sadly died.
“We, along with the Food Standards Agency, colleagues in local authorities and the NHS, have worked quickly to determine the likely cause of this outbreak and taken action to reduce the risk to the public’s health.
“To date, there have been no associated cases identified outside healthcare organisations, and any risk to the public is low.”
Colin Sullivan, the FSA’s chief operating officer, said: “Our sympathies are with the families of those patients who have tragically passed away.
“We have taken action along with local authorities to minimise the risk based on the evidence so far. The FSA will continue to investigate how the outbreak occurred and if further steps are required to protect vulnerable groups.”
Listeria has such a long incubation period and can withstand cold temperatures such as refrigeration and even freezing.
PHE, the FSA, Public Health Wales, Food Standards Scotland and Health Protection Scotland and a number of local authorities are investigating the outbreak.